You do not require a doctor's sickness certificate for any illness lasting seven days or less. Your employer may however require you to complete a self-certification form (SC2) which is available from your employer or on the HMRC website.
Evidence that you are sick
If you are sick for more than seven days, your employer can ask you to give them some form of medical evidence to support payment of SSP (statutory sick pay).
It is up to your employer to decide whether you are incapable of work. A medical certificate, now called a 'Statement of Fitness for Work’ (see below) from your doctor is strong evidence that you are sick and would normally be accepted, unless there is evidence to prove otherwise.
You could also provide evidence from someone who is not a medical practitioner, e.g. a dentist. Your employer will decide whether or not this evidence is acceptable. If your employer has any doubts, they may still ask for a medical certificate from your GP.
Statement of Fitness for Work - ’Fit Note'
The 'fit note' was introduced on 6 April 2010. With your employer's support, the note will help you return to work sooner by providing more information about the effects of your illness or injury.
For more information see the DirectGov website (where this information was sourced).
Requests for certification of absence from the workplace relating to COVID-19:
1. Symptomatic so isolating for 7 days
Patients can and should self-certify for the first 7 days as normal if they are unfit to work (see the above form). You do NOT need to contact your GP.
2. Symptomatic AND remaining unwell for OVER 7 days
If you remain unwell and unfit to work after 7 days, the current advice is to visit www.111.nhs.uk where there is an online self-assessment tool. You do NOT need to contact your GP for a certificate but you can use this template (COVID-19 Certification of Sickness PDF)
3. Household contact symptoms so isolating for 14 days as per government advice
Doctors can only provide certificates for the purpose of illness, not in relating to government advice regarding self-isolation. Employers are responsible for putting in place arrangements for home/remote working where possible. Where it is not, the employee may self-certify and return to work following the relevant absence which their employer may authorise as per government advice.
4. At risk group so following government advice
Where patients do become unwell during or after this time, point 1 and 2 applies. You do NOT need to contact your GP - you can use the attachment from point 2)
5. Those in full time education who are symptomatic OR requiring self-isolation
There is no NHS requirement to issue certification to schools or colleges to confirm absence. The schools must work with parents and students to ensure absence is appropriately recorded. You do NOT need to contact your GP.